[PATCH v3] net: ethernet: davicom: fix devicetree irq resource

[PATCH v3] net: ethernet: davicom: fix devicetree irq resource

[Robert Jarzmik]

The dm9000 driver doesn't work in at least one device-tree
configuration, spitting an error message on irq resource :
[    1.062495] dm9000 8000000.ethernet: insufficient resources
[    1.068439] dm9000 8000000.ethernet: not found (-2).
[    1.073451] dm9000: probe of 8000000.ethernet failed with error -2

The reason behind is that the interrupt might be provided by a gpio
controller, not probed when dm9000 is probed, and needing the probe
deferral mechanism to apply.

Currently, the interrupt is directly taken from resources. This patch
changes this to use the more generic platform_get_irq(), which handles
the deferral.

Moreover, since commit Fixes: 7085a7401ba5 ("drivers: platform: parse
IRQ flags from resources"), the interrupt trigger flags are honored in
platform_get_irq(), so remove the needless code in dm9000.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Marcel Ziswiler <marcel@ziswiler.com>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
---
Since v1: comment style and requested irq test < 0
          David, you should know that Sergei is concerned with the
	  subsystem prefix in the patch subject (too long for him).
Since v2: leak of the ethernet device
---
 drivers/net/ethernet/davicom/dm9000.c | 34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/davicom/dm9000.c b/drivers/net/ethernet/davicom/dm9000.c
index cf94b72dbacd..48d91941408d 100644
--- a/drivers/net/ethernet/davicom/dm9000.c
+++ b/drivers/net/ethernet/davicom/dm9000.c
@@ -128,7 +128,6 @@ struct board_info {
 	struct resource *data_res;
 	struct resource	*addr_req;   /* resources requested */
 	struct resource *data_req;
-	struct resource *irq_res;
 
 	int		 irq_wake;
 
@@ -1300,22 +1299,16 @@ static int
 dm9000_open(struct net_device *dev)
 {
 	struct board_info *db = netdev_priv(dev);
-	unsigned long irqflags = db->irq_res->flags & IRQF_TRIGGER_MASK;
 
 	if (netif_msg_ifup(db))
 		dev_dbg(db->dev, "enabling %s\n", dev->name);
 
-	/* If there is no IRQ type specified, default to something that
-	 * may work, and tell the user that this is a problem */
-
-	if (irqflags == IRQF_TRIGGER_NONE)
-		irqflags = irq_get_trigger_type(dev->irq);
-
-	if (irqflags == IRQF_TRIGGER_NONE)
+	/* If there is no IRQ type specified, tell the user that this is a
+	 * problem
+	 */
+	if (irq_get_trigger_type(dev->irq) == IRQF_TRIGGER_NONE)
 		dev_warn(db->dev, "WARNING: no IRQ resource flags set.\n");
 
-	irqflags |= IRQF_SHARED;
-
 	/* GPIO0 on pre-activate PHY, Reg 1F is not set by reset */
 	iow(db, DM9000_GPR, 0);	/* REG_1F bit0 activate phyxcer */
 	mdelay(1); /* delay needs by DM9000B */
@@ -1323,7 +1316,8 @@ dm9000_open(struct net_device *dev)
 	/* Initialize DM9000 board */
 	dm9000_init_dm9000(dev);
 
-	if (request_irq(dev->irq, dm9000_interrupt, irqflags, dev->name, dev))
+	if (request_irq(dev->irq, dm9000_interrupt, IRQF_SHARED,
+			dev->name, dev))
 		return -EAGAIN;
 	/* Now that we have an interrupt handler hooked up we can unmask
 	 * our interrupts
@@ -1500,15 +1494,22 @@ dm9000_probe(struct platform_device *pdev)
 
 	db->addr_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	db->data_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
-	db->irq_res  = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 
-	if (db->addr_res == NULL || db->data_res == NULL ||
-	    db->irq_res == NULL) {
-		dev_err(db->dev, "insufficient resources\n");
+	if (!db->addr_res || !db->data_res) {
+		dev_err(db->dev, "insufficient resources addr=%p data=%p\n",
+			db->addr_res, db->data_res);
 		ret = -ENOENT;
 		goto out;
 	}
 
+	ndev->irq = platform_get_irq(pdev, 0);
+	if (ndev->irq < 0) {
+		dev_err(db->dev, "interrupt resource unavailable: %d\n",
+			ndev->irq);
+		ret = ndev->irq;
+		goto out;
+	}
+
 	db->irq_wake = platform_get_irq(pdev, 1);
 	if (db->irq_wake >= 0) {
 		dev_dbg(db->dev, "wakeup irq %d\n", db->irq_wake);
@@ -1570,7 +1571,6 @@ dm9000_probe(struct platform_device *pdev)
 
 	/* fill in parameters for net-dev structure */
 	ndev->base_addr = (unsigned long)db->io_addr;
-	ndev->irq	= db->irq_res->start;
 
 	/* ensure at least we have a default set of IO routines */
 	dm9000_set_io(db, iosize);
-- 
2.1.4

Re: [PATCH v3] net: ethernet: davicom: fix devicetree irq resource

[Sergei Ianovich]

On Sat, 2016-02-20 at 21:45 +0100, Robert Jarzmik wrote:
> The dm9000 driver doesn't work in at least one device-tree
> configuration, spitting an error message on irq resource :
> [    1.062495] dm9000 8000000.ethernet: insufficient resources
> [    1.068439] dm9000 8000000.ethernet: not found (-2).
> [    1.073451] dm9000: probe of 8000000.ethernet failed with error -2
> 
> The reason behind is that the interrupt might be provided by a gpio
> controller, not probed when dm9000 is probed, and needing the probe
> deferral mechanism to apply.
> 
> Currently, the interrupt is directly taken from resources. This patch
> changes this to use the more generic platform_get_irq(), which
> handles
> the deferral.
> 
> Moreover, since commit Fixes: 7085a7401ba5 ("drivers: platform: parse
> IRQ flags from resources"), the interrupt trigger flags are honored
> in
> platform_get_irq(), so remove the needless code in dm9000.
> 
> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
> Acked-by: Marcel Ziswiler <marcel@ziswiler.com>
> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
> 

Tested-by: Sergei Ianovich <ynvich@gmail.com>

I've hit the original bug too. This patch fixes the *regression*. It
may be worth adding a note about this.

-- 
Sergei Ianovich <ynvich@gmail.com>

Re: [PATCH v3] net: ethernet: davicom: fix devicetree irq resource

[David Miller]

From: Robert Jarzmik <robert.jarzmik@free.fr>
Date: Sat, 20 Feb 2016 21:45:26 +0100

> The dm9000 driver doesn't work in at least one device-tree
> configuration, spitting an error message on irq resource :
> [    1.062495] dm9000 8000000.ethernet: insufficient resources
> [    1.068439] dm9000 8000000.ethernet: not found (-2).
> [    1.073451] dm9000: probe of 8000000.ethernet failed with error -2
> 
> The reason behind is that the interrupt might be provided by a gpio
> controller, not probed when dm9000 is probed, and needing the probe
> deferral mechanism to apply.
> 
> Currently, the interrupt is directly taken from resources. This patch
> changes this to use the more generic platform_get_irq(), which handles
> the deferral.
> 
> Moreover, since commit Fixes: 7085a7401ba5 ("drivers: platform: parse
> IRQ flags from resources"), the interrupt trigger flags are honored in
> platform_get_irq(), so remove the needless code in dm9000.
> 
> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
> Acked-by: Marcel Ziswiler <marcel@ziswiler.com>

Applied.